The Intrusion Detection System can monitor and investigate the harmful actions on a network and take necessary action to halt the external data. If the external request arrives, the IDS technique notifies the user about the intruders and thereby, allows the user to disconnect the IP network connection and reset the network connection from any interrupt. Hence, various anomaly based IDSs used for providing cyber security are reviewed in this paper. Accordingly, various research papers based on anomaly detection are reviewed by providing a classification based on several aspects, and are analyzed regarding various factors, such as datasets utilized, accuracy obtained, evaluation metrics, and implementation tools. From the analysis, it is observed that majority of the papers reviewed have employed MATLAB as the implementation tool.